Medical radiographic imaging systems may apply radiation, such as x-rays, to a patient and detect radiation passing through the patient to obtain a radiographic image for diagnosis. In recent years, flat panel-type detectors have been used to detect a radiation image of a patient irradiated by a source (e.g., an x-ray tube). For some radiographic exams, multiple exposures may be needed to form an extended field of a long length image, due to the image detector having a smaller size than the long length image desired. Some types of desired exams associated with this type of extended field of view capture are exams such as: spine and scoliosis, long leg, and whole body imaging.
For example, traditional indirect forms of x-ray capture for such multiple captures may be achieved by overlapping multiples of analog x-ray film or re-useable computed radiography (CR) imaging plates, orienting them in one long length arrangement. Then a single exposure may be taken to expose all the capture areas at the same time. Resulting individual images can be processed separately (one at time) to transfer them to a processing workstation to be connected or stitched together.
In recent years, x-ray capture devices (e.g., detectors) have included portable electronic flat panel detectors which are directly connected (wired or wirelessly) to the workstation for immediate image transfer to the workstation (e.g., this provides “direct x-ray capture”). However, detectors may be significantly more expensive than film and it is less common to have multiple detectors. In addition, from the mechanical characteristics of their design it is not currently feasible to overlap them for a single long length exposure capture, since they consist of elaborate electronic components and surrounding structural hardware. Also an extended long sized (e.g., direct long length) detector may not be feasible for user versatility or cost.
This means that a long length capture requires separate multiple captures or images at sequential detector positions. Capturing multiple images separately introduces challenges in moving the detector behind the patient between each exposure. For example, upright x-ray exams are commonly performed using an upright or chest detector stand with some type of detector or image capture device inside. These upright devices feature the ability to position the detector at various heights depending on anatomy of interest and patient size. Some exams require multiple images at different heights to view a longer area of interest. It is preferable for these multiple images to be connected or “stitched” together as one extended length image.